DESCRIPTION: A randomized clinical trial and a pilot study are proposed. The objectives of the randomized clinical trial are to determine if antibodies to T cells and/or switching maintenance immunosuppression, when administered at the time of a biopsy-proven primary rejection episode, will significantly decrease the incidence of a second rejection and chronic rejection in kidney transplant recipients. The investigators will modify immunosuppression at the time of the first rejection episode by substituting OKT3 for steroid therapy and/or substituting mycophenolate for azathioprine or FK506 for Cyclosporine-A. The objective of the pilot study is to determine if early steroid withdrawal is tolerated by recipients of living, related donor transplants who are receiving Cyclosporine-A, mycophenolate, and Prednisone and have not had a rejection episode. Steroids will be withdrawn over a two week period three months after transplant. The primary endpoint will be the incidence of biopsy-proven rejection within six months of steroid withdrawal. If early steroid withdrawal is tolerated in this pilot study, a second pilot study will test the feasibility of withdrawing steroids at four weeks, and if this pilot is successful a third pilot will test the feasibility of administering steroids only during the perioperative period. If this series of pilot studies shows that steroids can be withdrawn with no increase in biopsy-proven rejection the consortium members plan to conduct a prospective randomized clinical trial. If any of the pilots fail, the consortium will proceed with a prospective randomized trial of the previous pilot.